code reuse: wich is the best approach for sharing controllers and views between different projects?

[eluser]Aken[/eluser]
If you are hosting all of these sites off of the same server / CI install, Packages might be useful for you.

The way I would set it up, the MY_Controller would have the logic for figuring out what website is being called, and then call all of that website's relevant files / info.

It really depends on your end goal, how much is and isn't shared between the websites. That's the nice thing about Packages, because they can contain configs, controllers, views, etc., all in individual folders for easy compartmentalization.